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LOWER CRETACEOUS, 93

Here there is a marked unconformity between the Patuxent for-
mation, consisting of the usual compact, partially indurated, drab,
sandy clays and light-gray, arkosic and micaceous sands, and the over-
lying laminated sands and clays of the Black Creek formation.

That the unconformable relations existing between the Patuxent
and Black Creek formations are very marked is further proven by
observations made at Hairs Wood Landing, 14 mile below milepost 99.
In a section extending for several hundred yards along the left bank
the only materials seen are those belonging to the Patuxent forma-
tion and to the Pleistocene, the former consisting of the usual com-
pact sands and clays rising some 20 or 25 feet above low-water level,
and the latter consisting of characteristic sands and clays with a thin
gravel band at base. The laminated materials of the Black Creek

formation are entirely absent. At Devanes Ferry, however, just above

milepost 98, left bank, the Black Creek beds are again seen resting un-
conformably upon the Patuxent beds. This is the last section in which
the beds of this formation appear. ;

In Johnston County exposures of typical Patuxent strata occur in
cuts of the Atlantic Coast Line Railroad in the vicinity of the village
of Four Oaks. In one of these 414 miles southwest of the depot sands
and clays, with a line of quartz and schist fragments along the base,
belonging to the Patuxent formation, were observed in contact with
deeply decayed crystalline schists. This is one of the few places where
the contact of the formation with the underlying basement rocks has
been observed.

Tn a cut 5 miles southwest of Four Oaks the unconformable relation
of the Patuxent, of the Lower Oretaceous, to the overlying Pleistocene
is well exhibited. A similar exposure occurs in a cut 234 miles north-
east of Four Oaks, as represented in the section (Fig. 3) on page 94.

Occasional exposures occur in Johnston County in the hills for sev-
eral miles to the south and southeast of Four Oaks, and one good out-
crop occurs about 21% miles northwest of Four Oaks in the road leading
from Black Creek up to Clements Church. .

On Neuse River various exposures of the Patuxent formation occur

from 1 mile above Cox’s Bridge in Johnston County to the Atlan-

tie Coast Line Railroad bridge southwest of Goldsboro in Wayne
County. These occurrences are all low, the beds not rising more than
8 or 10 feet above extreme low water. Throughout this distance the
Patuxent strata are overlain unconformably by overlapping beds of
the Black Oreek formation, except where the latter have been removed